Asymmetric nonlinear-mode-conversion in an optical waveguide with PT symmetry  

作　　者：Changdong Chen Youwen Liu Lina Zhao Xiaopeng Hu Yangyang Fu 

机构地区：[1]College of Physics,Nanjing University of Aeronautics and Astronautics,Nanjing 211100,China [2]Key Laboratory of Aerospace Information Materials and Physics(NUAA),MIIT,Nanjing 211106,China [3]Collaborative Innovation Center of Light Manipulations and Applications,Shandong Normal University,Jinan 250358,China [4]National Laboratory of Solid State Microstructures,College of Engineering and Applied Sciences,and School of Physics,Nanjing University,Nanjing 210093,China

出　　处：《Frontiers of physics》2022年第5期183-190,共8页物理学前沿（英文版）

基　　金：This work was supported by the National Natural Science Foundation of China(Grant Nos.11904169 and 91950106);the Fundamental Research Funds for the Central Universities(Grant No.NE2022007);the Natural Science Foundation of Jiangsu Province(No.BK20190383);Postdoctoral Science Foundation of Jiangsu Province(No.2020Z224),China Postdoctoral Science Foundation(No.2020M681576);the Top-notch Academic Programs Project of Jiangsu Higher Education Institutions。

摘　　要：Asymmetric mode transformation in waveguide is of great significance for on-chip integrated devices with one-way effect,while it is challenging to achieve asymmetric nonlinear-mode-conversion(NMC)due to the limitations imposed by phase-matching.In this work,we theoretically proposed a new scheme for realizing asymmetric NMC by combining frequencydoubling process and periodic PT symmetric modulation in an optical waveguide.By engineering the one-way momentum from PT symmetric modulation,we have demonstrated the unidirectional conversion from pump to second harmonic with desired guided modes.Our findings offer new opportunities for manipulating nonlinear optical fields with PT symmetry,which could further boost more exploration on on-chip nonlinear devices assisted by non-Hermitian optics.

关 键 词：nonlinear mode conversion meta-grating PT symmetry optical waveguide 

分 类 号：O43[机械工程—光学工程]